The project includes three areas of study: 1) The development of instruments sensitive to the presence of pain in patients with cancer, its severity, and impact on the patient, and to use these instruments to conduct a cross sectional study of pain in patients with cancer at four sites. Pain data obtained from those patients is being contrasted to pain in patients with other diseases. 2) The development of methods of reliability determining the physical basis of pain in cancer patients, including physical indicators of pain, such as non-verbal pain behavior and endogenous peptides, and 3) The study of attitudes of health professionals and lay persons towards cancer pain, its treatment, and the relationship of pain and its treatment to the progression of the disease.